/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.evaluation.value;

import proguard.classfile.*;

/**
 * This class provides methods to create and reuse Value objects. Its ReferenceValue objects have types.
 *
 * @author Eric Lafortune
 */
public class TypedReferenceValueFactory extends BasicValueFactory {
    static final ReferenceValue REFERENCE_VALUE_NULL = new TypedReferenceValue(null, null, false, true);
    static final ReferenceValue REFERENCE_VALUE_JAVA_LANG_OBJECT_MAYBE_NULL =
        new TypedReferenceValue(ClassConstants.NAME_JAVA_LANG_OBJECT, null, true, true);
    static final ReferenceValue REFERENCE_VALUE_JAVA_LANG_OBJECT_NOT_NULL =
        new TypedReferenceValue(ClassConstants.NAME_JAVA_LANG_OBJECT, null, true, false);

    // Implementations for BasicValueFactory.

    public ReferenceValue createReferenceValueNull() {
        return REFERENCE_VALUE_NULL;
    }

    public ReferenceValue createReferenceValue(String type, Clazz referencedClass, boolean mayBeExtension,
        boolean mayBeNull) {
        return type == null ? REFERENCE_VALUE_NULL
            : !type.equals(ClassConstants.NAME_JAVA_LANG_OBJECT) || !mayBeExtension
                ? new TypedReferenceValue(type, referencedClass, mayBeExtension, mayBeNull)
                : mayBeNull ? REFERENCE_VALUE_JAVA_LANG_OBJECT_MAYBE_NULL : REFERENCE_VALUE_JAVA_LANG_OBJECT_NOT_NULL;
    }

    public ReferenceValue createArrayReferenceValue(String type, Clazz referencedClass, IntegerValue arrayLength) {
        return createArrayReferenceValue(type, referencedClass, arrayLength,
            createValue(type, referencedClass, true, true));
    }

    public ReferenceValue createArrayReferenceValue(String type, Clazz referencedClass, IntegerValue arrayLength,
        Value elementValue) {
        return createReferenceValue(ClassConstants.TYPE_ARRAY + type, referencedClass, false, false);
    }
}